#back{
    width: 50px;
    height: 50px;
    background-color: rgb(243, 247, 13);
    color: #fff;
    font-size: 55px;
    border-radius: 10px;
    text-align: center;
    position: fixed;
    right: 50px;
    bottom: 10px;
    background-repeat: no-repeat;
}
body{
    background-color: rgb(23, 54, 233);
}
.container{
    background-color: #fff;
}
.copyright{
    text-align: center;
    color: rgb(200, 212, 26);
}
.all{
    padding: 0;
    background-color: #fff;
}
.content{
    padding: 10px;
}
.jumbotron{
    color: rgb(13, 13, 14);
    background-color:#fff;
}